foo.cc: In function 'int main()':
foo.cc:51:8: warning: 'y' may be used uninitialized in this function [-Wmaybe-uninitialized]
   51 |     dfs(x,y);
      |     ~~~^~~~~
foo.cc:51:8: warning: 'x' may be used uninitialized in this function [-Wmaybe-uninitialized]

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